Pencil.



APHENNIIGER.

PEN OIL. APPLICATION rum) M11112. zoos.

7H: NoR'Rrs PETERS c0 'wnsumamu, o. c,

PATENTED MAR. 26, 1907.

ADOLF I-IENNIGER, OF BERLIN, GERMANY.

PENCIL.

Specification of Letters Patent.

Patented March 26, 1907.

Application filed January 12,1905. Serial No. 240,847.

To all whom I??? may concern:

Be it known that I, ADoLF I-IENNIGER, ma-

chinist, a subject of the Emperor of Germany, and residing at 64Gartenstrasse, Berlin, N in the German Empire, have invented certain newand useful Improvements in Pencils, of which the following is aspecification.

This invention relates to a pencil consisting of a pigmentfor instance,graphite firmly inclosed in a protecting-mantle of an artificially-madesolid material.

More particularly, the invention has for its object an improvedprotecting-mantle of said kind and an improved process of manufacturingsame.

My new protecting-mantle for pencils consists of the dry residuum ofstarch containing parts of vegetables, especially of bulbous plants,such as potatoes, cemented together by some cements and being intermixedwith fibrous material Besides these components the mantle mass maycontain other admixtures, such as coloring material or substances,adapted to increase the elasticity of the mass, &c. In order to make themass somewhat spongy, I may use an addition of starch. However, thecontents in starch is generally disadvantageous, in so far as it raisesthe price of the mass.

If potatoes are used as raw material for my new pencil-protectingmantle, I may proceed as follows: A part of the potatoes, for instance,one-half, is boiled. These potatoes are then squashed. into a pulp. Alsothe raw potatoes are converted into a pulpy mass but prior to that it isadvisable to merely cut them into pieces of a certain size and to exposethem to the action of a diluted acid. or of alkaline solutions, wherebyany bacteria in the same will be killed and may be comtinations formedwhich act as cements. Very good results have been obtained by treatingthe potato-pieces with four per cent. acetic acid from three totwenty-four hours. How ever, the concentration of the solution and theduration of treatment may be varied within wide ranges. After the acidtreatment the mass is washed out with water. Residues of acid may beneutralized by alkali. Hereafter the potato-pieces are dried and dividedinto a pulp. To the pulp or powder of boiled and raw potatoes a suitablecement is added-for instance, seven per cent. of ordinary glue--and afew per cent. of a fibrous materialfor instance, four per cent. of thewaste products of cotton spinning and weaving mills. I also like to addsubstances adapted to increase the elasticityfor instance, two to threeper cent. beeswax. The whole mass is then thoroughly mixed. Thereuponthe mixture is compressed and will then form a solid mass of whichprotecting-mantles for pencils can be made. It is advisable to compressthe mass in a somewhat heated condition, as it has been found that thecompactness of the same is greater if the compressing takes place at atemperature of about centigrade than in the case of cold pressing. Alsothe resulting surfaces are smoother, so that a special olishing processmay be dispensed with. T e forming of the mantle of out the mass ispreferably eifected simultaneously with the formation of the mass itselfby pressing the mixed raw materials (triturated potatoes, glue, and soon) out of a mold in the shape of a hollow rope. Into the hole in therope the core of the pencil containing the pigment can then be inserted.On. the mass getting dry it is so contracted that the core of the pencilis firmly inclosed in the same provided the cross-section of the hole isof a corresponding size.

Instead of glue other binders may be used. Also instead of beeswaxresin, grease, or mixtures of these substances or other substances maybe used for increasing the elasticity of the mass. Moreover, instead ofthe said fibrous material wood-pulp or other suitable substances may beused. Instead of the potato mass the mass of other bulbous plants maybeused. The use ofother parts of plants containing amylum is not excludedeither, though thus far potato mass has given the best results and hasproved the least expensive. Instead of using parts of plants in theirnatural state waste products may also be, used. Such waste products, forinstance, are the residues of distilleries and starch factories. TheseWaste products may also be added to the natural amyleceous parts ofplantsfor instance, to the potatoes in the above-described process.

The new pencil is illustrated by the accompanying drawing, partly inside elevation and partly in longitudinal section.

The mantle of the pencil is indicated by the reference-letter a, and thecore by the letter I).

What I claim as my invention, and desire to secure by Letters Patent, is

1. A pencil for Writing, drawing and similar purposes comprising a coreand a mantle firmly inclosing same, said mantle containing starchcontaining vegetables in compressed condition preferably in combinationWith suitable cement and fibrous material.

2. A pencil for writing, drawing and simi lar purposes comprising a coreand a mantle firmly inclosing same, said mantle containing dry residuumof vegetable bulbs in compressed condition preferably in combinationWith suitable cement and fibrous material.

3. A pencil for writing, drawing and similar purposes comprising a coreand a mantle firmly inclosing same, said mantle containing dry residuumof potatoes in compressed condition preferably in combination with suitable cement and fibrous material.

4. A pencil for Writing, drawing and simi lar purposes comprising a coreand a mantle firmly inclosing same, said mantle consisting 3 of thecompressed. substance of potatoes in admixture with vegetable fibers ofother origin and glue, wax, fat, oil or compounds.

6. A pencil for writing, drawing and similar purposes comprising a coreand a mantle firmly inclosing same, said mantle consisting of thecompressed substance of potatoes, at least a part of said potatoes beingin boiled condition, in admixture with vegetable fibers of other originand glue, wax, f at, oil or compounds.

In witness whereof I have hereunto set my hand in the presence of twowitnesses.

ADOLF HENNTGER. Witnesses:

HENRY Hxsrnn, VVOLDEMAR I'IAUP'I.

